Investment in ATC and ATC Holdco (Details-2) - ATC [Member] - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Schedule of Equity Method Investments [Line Items]
Operating revenues	$ 218,222	$ 203,776	$ 430,150	$ 404,202
Operating expenses	(109,197)	(101,517)	(214,039)	(200,593)
Other income, net	356	565	543	956
Interest expense, net	(36,040)	(33,504)	(71,458)	(66,414)
Earnings before members' income taxes	$ 73,341	$ 69,320	$ 145,196	$ 138,151